Fix data race in query factory initialisation

[o1egl]

Fixes #136

[codecov]

Codecov Report

Merging #133 into master will increase coverage by 0.06%.
The diff coverage is 100%.

@@           Coverage Diff            @@
##           master   #133      +/-   ##
========================================
+ Coverage   89.94%    90%   +0.06%     
========================================
  Files          47     47              
  Lines        3561   3563       +2     
========================================
+ Hits         3203   3207       +4     
+ Misses        324    322       -2     
  Partials       34     34

Impacted Files	Coverage Δ
database.go	89.82% <100%> (+1.33%)	⬆️

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[doug-martin]

For tracking purposes and if someone else is searching for answers related to this problem can you add a short description about the addition, and what your use case was?

[o1egl]

For tracking purposes and if someone else is searching for answers related to this problem can you add a short description about the addition, and what your use case was?

Done